The present invention relates to mechanical rotatable gongs useful for mounting on railroad car wheels to warn persons of the movement of a railroad car.
U.S. Pat. No. 1,225,036 (1917) to Kieren discloses an alarm for cars. A gong is eccentrically mounted on the hub of a railroad or mining car wheel. Inside the gong is mounted a gong sounding mechanism consisting of a cylindrical casing having inside a reciprocating metal ball. When the wheel rotates the metal ball reciprocates hitting a hammer at one end of the cylinder, thereby sounding the gong with each revolution of the wheel. The device is especially suited for mining carts, which move slowly in the dark.
The device is not suited for high-speed railroad car use because the gong would continue to sound even at high speeds. Such high speed gonging would only create noise pollution on each side of the moving train. Powerful whistles aimed forward are used to sound warnings of approaching high-speed trains.
The present invention embellishes the Kieren concept by centrally mounting a single-cylinder gong sounding mechanism. At about fifteen miles per hour the metal balls in a cylinder having a length along a diameter of the wheel are held against its hammer by centrifugal force. Therefore, the gong stops sounding at speeds over about fifteen miles per hour. Furthermore, when the gong does sound it offers two gongs for each rotation of the wheel, since the cylinder has a hammer at each end. This feature offers more sound as well as redundancy to provide functionality even after mechanical failure of an individual hammer.
The main aspect of the present invention is to provide an alarm gong on the rotating wheel of a vehicle which sounds only at low speeds.
Another aspect of the present invention is to provide mechanical redundancy for a simple gong sounding mechanism.
Another aspect of the present invention is to provide an universal mounting plate which fits several sized wheel stud bolts.
Another aspect of the present invention is to provide a dampener for a gong.
Other aspects of this invention will appear from the following description and appended claims, reference being made to the accompanying drawings forming a part of this specification wherein like reference characters designate corresponding parts in the several views.
The preferred embodiment teaches a cast aluminum, one cylinder striker housing with a hammer at each end. Other material choices include glass filled nylon or a molded polymer. The cylinder houses three balls, two end hammers and a return spring to retract the end hammer away from the gong after a strike. A gong surrounds the striker housing. The gong and striker housing mount to a universal mounting plate which in turn is fastened to a trio of wheel studs via nuts. As the train travels at a speed nominally set at fifteen miles per hour, the double hammers clang twice per wheel revolution. This double striking action provides mechanical backup since the gong will sound even with one hammer down. For speeds over fifteen miles per hour the metal balls are held against one end hammer by centrifugal force. Thus, no reciprocation of the metal balls occur, and no gonging occurs above this preset speed.